RESUMO
Plasmodium falciparum is the most lethal malaria parasite. The present study investigates the interaction capabilities of select plant derivatives, iso-mukaadial acetate (IMA) and ursolic acid acetate (UAA), against P. falciparum Hsp70-1 (PfHsp70-1) using in vitro approaches. PfHsp70-1 facilitates protein folding in the parasite and is deemed a prospective antimalarial drug target. Recombinant PfHsp70-1 protein was expressed in E. coli BL21 cells and homogeneously purified by affinity chromatography. The interaction between the compounds and PfHsp70-1 was evaluated using malate dehydrogenase (MDH), and luciferase aggregation assay, ATPase activity assay, and Fourier transform infrared (FTIR). PfHsp70-1 prevented the heat-induced aggregation of MDH and luciferase. However, the PfHsp70-1 chaperone role was inhibited by IMA or UAA, leading to both MDH and luciferase's thermal aggregation. The basal ATPase activity of PfHsp70-1 (0.121 nmol/min/mg) was closer to UAA (0.131 nmol/min/mg) (p = 0.0675) at 5 mM compound concentration, suggesting that UAA has no effect on PfHsp70-1 ATPase activity. However, ATPase activity inhibition was similar between IMA (0.068 nmol/min/mg) (p < 0.0001) and polymyxin B (0.083 nmol/min/mg) (p < 0.0001). The lesser the Pi values, the lesser ATP hydrolysis observed due to compound binding to the ATPase domain. FTIR spectra analysis of IMA and UAA resulted in PfHsp70-1 structural alteration for ß-sheets shifting the amide I band from 1637 cm-1 to 1639 cm-1, and for α-helix from 1650 cm-1 to 1652 cm-1, therefore depicting secondary structural changes with an increase in secondary structure percentage suggesting that these compounds interact with PfHsp70-1.
Assuntos
Proteínas de Choque Térmico HSP70/efeitos dos fármacos , Proteínas de Choque Térmico HSP70/metabolismo , Chaperonas Moleculares/metabolismo , Plasmodium falciparum/metabolismo , Triterpenos/farmacologia , Adenosina Trifosfatases/metabolismo , Antimaláricos/química , Antimaláricos/metabolismo , Antimaláricos/farmacologia , Escherichia coli/metabolismo , Plasmodium falciparum/efeitos dos fármacos , Estudos Prospectivos , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Ácido UrsólicoRESUMO
In an honors course on "Omics Sciences," draft genome sequences of Chryseobacterium elymi KCTC 22547T, Chryseobacterium flavum KCTC 12877T, Chryseobacterium hispanicum KCTC 22104T, Chryseobacterium lathyri KCTC 22544T, "Candidatus Chryseobacterium massiliae" CCUG 51329T, Chryseobacterium piscium CCUG 51923T, and Chryseobacterium rhizosphaerae KCTC 22548T were generated to facilitate phylogenomic comparisons within the genus.
